A lawsuit alleges that Mark Attanasio, the billionaire owner of the Milwaukee Brewers, has been illegally removing sand from Malibu’s Broad Beach and transporting it to his home for use in a construction project. The Los Angeles Times reports that James Kohlberg, Attanasio’s next-door neighbor and son of global investor Jerome Kohlberg, has filed the lawsuit. Kohlberg claims that Attanasio has been using excavators to extract sand from the public beach, restricting public access and contaminating the area with gasoline residue from the machinery, which poses a risk to local marine life.

The lawsuit states that although Attanasio was granted permits in March to repair a damaged seawall, excavators were seen removing sand from Broad Beach in June and July, leaving behind hazardous residue. The suit accuses Attanasio of creating both public and private nuisances and violating the California Coastal Act.

The lawsuit describes the situation as a misuse of public resources: “This case is about a private property owner using a public beach as their own personal sandbox and the disturbing conversion of a public natural resource (i.e., sand from Broad Beach) for a nearby homeowner’s personal, private use.”

Kenneth Ehrlich, the attorney representing Mark Attanasio, asserts that Attanasio’s company has fully complied with all permits issued by the city of Malibu and Los Angeles County. Attanasio purchased his property on Broad Beach for $23 million in 2007.